EHEC outbreak: update 11
The outbreak remains primarily centred in Germany, and investigations continue into the nature of the unusual Escherichia coli bacteria serotype and its source.
Haemolytic uraemic syndrome (HUS)
As of 7 June at 15:00 CET, Germany had reported 689 HUS cases (including 18 fatalities): 47 more cases and 3 additional deaths than the previous day. 69% of cases were in females and 87% in adults aged 20 years or older, with the highest attack rates per 100 000 population in the group aged 20–49 years. Case-onset dates ranged from 1 May to 4 June.
Enterohaemorrhagic Escherichia coli (EHEC)
As of 7 June at 15:00 CET, 1959 cases of EHEC infection (without HUS) had been reported in Germany (6 fatal, as 1 death reported yesterday had not been confirmed): 276 more than the previous day. 60% of cases were in females and 88% in adults aged 20 years or older. Case onset dates ranged from 1 May to 4 June.
The Robert Koch Institute, in Germany, states that the current HUS and EHEC notification data, as well as data from the surveillance of bloody diarrhoea in emergency departments, show an overall decreasing trend in the number of cases. It is uncertain whether this decline is due to changes in consumption of raw vegetables and/or to the waning of the source of infection.
As of 7 June at 23:00 CET, 12 other European countries had reported a total of 33 HUS cases (1 fatal) and 64 EHEC cases (none fatal). There were 2 more HUS cases and 9 fewer EHEC cases reported than the previous day. As the revised European Union (EU) case definition is being applied, a number of cases reported earlier have been excluded:
* 7 cases of bloody diarrhoea have yet to be confirmed.
In addition, the Centers for Disease Control and Prevention (CDC) in Atlanta, United States of America have published information on 3 HUS cases (1 confirmed and 2 suspected) and 1 suspected EHEC case (without HUS) in the United States linked to this outbreak. On 7 June, the Public Health Agency of Canada reported on 1 suspected case of E. coli O104 infection (without HUS), in a person with travel history to northern Germany and with links to a confirmed case of E. coli O104 infection in Germany.
All but one of the above HUS and EHEC cases were in people who had travelled to or lived in Germany during the incubation period for infection, typically 3–4 days after exposure (range: 2–10 days). An increasing number of cases is laboratory confirmed as EHEC serotype O104:H4, or more precisely a strain of enteroaggregative verocytotoxin-producing E. coli (EAggEC VTEC) O104:H4.
Investigations continue into the source of the outbreak.
EHEC and HUS have exclusive notification categories, so case numbers should not overlap. The figures in any rapidly evolving outbreak, however, are provisional and subject to change for a variety of reasons.
In providing the above information, WHO wishes to recognize the contribution of its Member States, and technical partners such as the European Commission, the European Centre for Disease Prevention and Control and a number of WHO collaborating centres.